Class: Ticketing::Ticket

Inherits:
Object
  • Object
show all
Defined in:
lib/ticketing/broker.rb

Overview

An acquired lock guard.

The lock is released when #release is called, or in the background when the ticket is #closed. If the client dies before releasing, the server's lease eventually frees it.

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(broker, conn, key, token, logger) ⇒ Ticket

Returns a new instance of Ticket.



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# File 'lib/ticketing/broker.rb', line 176

def initialize(broker, conn, key, token, logger)
  @broker = broker
  @conn = conn
  @key = key
  @token = token
  @logger = logger
  @released = false
  @mutex = Mutex.new
end

Instance Attribute Details

#key ⇒ Object (readonly)

The locked key.



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# File 'lib/ticketing/broker.rb', line 169

def key
  @key
end

#token ⇒ Object (readonly)

The fencing token for this grant — a value that strictly increases with every acquisition of any key. Pass it to the resource you protect and reject stale (lower) tokens.



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# File 'lib/ticketing/broker.rb', line 174

def token
  @token
end

Instance Method Details

#close ⇒ Object

Releases the lock in the background if it was not already released.



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# File 'lib/ticketing/broker.rb', line 194

def close
  should_release =
    @mutex.synchronize do
      next false if @released

      @released = true
      true
    end
  return unless should_release

  Thread.new do
    begin
      @broker.release_lock(@conn, @key)
    rescue StandardError
      @logger.error("auto-release #{@key} failed — lease will expire it")
    end
  end
  nil
end

#release ⇒ Object

Releases the lock. Returns true if the server still held it, false if it had already expired.



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# File 'lib/ticketing/broker.rb', line 188

def release
  @mutex.synchronize { @released = true }
  @broker.release_lock(@conn, @key)
end